macbook air whatsup spelling check

Hello marcingolf,

Welcome to the Apple Support Communities. From your post, something about spellcheck isn't working. We'll do what we can to help.

Verify that all the right settings in System Preferences are turned on. If they are turned on, try turning them off, restarting your Mac, then turning them back on again: Check spelling and grammar on Mac

Since it's only in a specific app, try removing that app then reinstalling it back on your Mac: Install and uninstall apps from the internet or disc on Mac

If you're still seeing the same issue, let us know what specifically is happening with spellcheck in that app.

Take care.

marcingolf,

The next best thing to do is try safe mode: How to use safe mode on your Mac

If those apps require special permissions to allow spellcheck, you might also want to check the Privacy section of System Preferences and enable those apps: Change Privacy preferences on Mac

If you're still having issues, it would be best to reach out to the developers of those apps for further help since it's only happening in those apps.

Cheers.